This relates to structures for providing electromagnetic shielding for circuits such as radio-frequency circuits.
Electronic devices such as computers, cellular telephones, and other devices often contain circuitry that requires electromagnetic shielding. For example, some electronic devices include radio-frequency transceiver circuits. Electronic devices may also include memory and other components that use clocks. If care is not taken, signals from one circuit may interfere with the proper operation of another circuit. For example, a clock signal or a clock signal harmonic that falls within the operating band of a radio-frequency receiver may cause undesirable interference for the receiver.
To prevent disruption from electromagnetic interference, circuits such as transceivers may be enclosed within metal radio-frequency (RF) shielding cans. The metal of the shielding cans blocks radio-frequency signals and helps shield the enclosed components from electromagnetic interference (EMI). In a typical configuration, integrated circuits are covered by RF shielding cans after being mounted on a printed circuit board.
Conventional arrangements in which RF shielding cans are mounted to a printed circuit board can help to reduce electromagnetic interference, but may be undesirably bulky. This may limit the effectiveness of RF shielding can arrangements in complex board designs in which numerous sections of the board require individual shielding.
It would therefore be desirable to provide improved radio-frequency shielding structures.